Effect on bond strength and collagen degradation of experimental dentin adhesives containing calcium orthophosphate particles

Abstract

The synthesis of dicalcium phosphate dihydrate (DCPD) functionalized with acidic monomers (DEGDMA, citric acid, acrylic acid and methacryloyloxyethyl phosphate) is being investigated to obtain non-agglomerated nanoparticles with high chemical interaction with dimethacrylate-based resin matrices. Although the use of calcium phosphate particles on dental composites is widely studied, the application of these particles on dental adhesives deserves further investigation. Therefore, this project aims to evaluate different experimental dental adhesives formulated with DCPD particles (functionalized with DEGDMA or citric acid) on microtensile bond strength (initial and after three months in simulated body fluid) and enzymatic activity at the dentin-adhesive interface via in situ zymography assay (after storage in buffer solution for 24 hours and three months). Dentin remineralization will be evaluated semi-quantitatively by scanning electron microscopy of the bonded interfaces and by dispersive x-ray spectroscopy. An adhesive without DCPD will be used as control. Data will be subjected to two-way ANOVA. In all cases, Tukey test will be used for pair-wise comparisons. The global significance level (±) will be set at 0.05. (AU)